开发中使用mongoTemplate进行Aggregation聚合查询

笔记:使用mongo聚合查询(一开始根本没接触过mongo，一点一点慢慢的查资料完成了工作需求)

需求：在订单表中，根据buyerNick分组，统计每个buyerNick的电话、地址、支付总金额以及总商品数，返回结果是CustomerDetail。

/*
 * project:列出所有本次查询的字段，包括查询条件的字段和需要搜索的字段；
 * match:搜索条件criteria
 * unwind：某一个字段是集合，将该字段分解成数组
 * group：分组的字段，以及聚合相关查询
 * 		sum：求和(同sql查询)
 * 		count：数量(同sql查询)
 * 		as:别名(同sql查询)
 * 		addToSet：将符合的字段值添加到一个集合或数组中
 * sort：排序
 * skip&limit：分页查询
 */
public List<CustomerDetail> customerDetailList(Integer pageNum,String userId,String buyerNick,String itemId,List<String> phones) throws Exception{
	Criteria criteria = Criteria.where("userId").is(userId);
	Integer pageSize = 10;
	Integer startRows = (pageNum - 1) * pageSize;
	if(buyerNick != null && !"".equals(buyerNick)){
		criteria.and("buyerNick").is(buyerNick);
	}
	if(phones != null && phones.size() > 0){
		criteria.and("mobile").in(phoneList);
	}
	if(itemId != null && !"".equals(itemId)){
		criteria.and("orders.numIid").is(itemId);
	}
	Aggregation customerAgg = Aggregation.newAggregation(
			Aggregation.project("buyerNick","payment","num","tid","userId","address","mobile","orders"),
			Aggregation.match(criteria),<br />　　　　　　　　　　　　　　 Aggregation.unwind("orders"),
			Aggregation.group("buyerNick").first("buyerNick").as("buyerNick").first("mobile").as("mobile").
			first("address").as("address").sum("payment").as("totalPayment").sum("num").as("itemNum").count().as("orderNum"),
			Aggregation.sort(new Sort(new Sort.Order(Sort.Direction.DESC, "totalPayment"))),
			Aggregation.skip(startRows),
			Aggregation.limit(pageSize)
			);
	List<CustomerDetail> customerList = tradeRepository.findAggregateList(new Query(criteria), userId, customerAgg,CustomerDetail.class);
	return customerList;
}

public <T> List<T> findAggregateList(Query query,String userNickName, Aggregation aggregation,Class<T> clazz) {
	AggregationResults<T> aggregate = this.mongoTemplate.aggregate(aggregation, collectionName, clazz);
	List<T> customerDetails = aggregate.getMappedResults();
	return customerDetails;
}

Trade表：

public class TradeInfo{
	private String tid;//订单id
	private Double payment;//支付金额
	private String buyerNick;//买家昵称
	private String address;//地址
	private String mobile;//手机号
	private Long num;//购买商品数量
	private List<order> orders;子订单
}

CustomerDetail：

public class CustomerDetail{
	private String buyerNick;//买家昵称
	private Double totalPayment;//订单金额
	private Integer orderNum;//订单数
	private Integer itemNum;//商品数
	private String address;//地址
}

OVER!